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1.
Vet Parasitol ; 277: 109020, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31896019

RESUMO

Haemonchus contortus is one of the most important gastrointestinal nematodes (GINs) infecting sheep, goats, and cattle worldwide. We developed a SYBR Green real-time PCR (qPCR) assay for detection and quantification of H. contortus by using specific primers based on a conserved region of the mitochondrial cytochrome oxidase subunit I (mt-COI) gene, and evaluated this technique in the detection of H. contortus infections in cattle in Central Anatolia Region of Turkey. The newly developed qPCR assay successfully discriminated H. contortus from other GIN species infecting cattle in the specificity evaluations, with a specific melt peak of 77.5 °C. Our results revealed the efficient amplification of the proposed target COI region within the range of plasmid copies, from 2 × 106 to 2 × 101 per µl, with 96.9 % efficiency, R² value of 0.999, and a slope of -3.398. Among the 920 cattle fecal samples from the field, 58 samples (6.3 %) were positive with qPCR assay, whereas 45 samples (4.9 %) were positive, as determined by larval culture, suggesting the utility of SYBR Green qPCR. Phylogenetic characterization of the partial COI gene of H. contortus isolates was also evaluated for 100 eggs and third stage larvae recovered from positive cattle faecal samples, which were verified with the qPCR assay prior to analyses. COI sequences were classified into three haplotypes (THC1 to THC3) with intraspecific nucleotide differences of 0.50 to 0.76 %. Phylogenetic analyses revealed that the haplotypes grouped with H. contortus isolates from several countries in a monophyletic cluster, with evidence of at least two main haplogroups. Overall, the SYBR Green qPCR assay was highly specific and sensitive, suggesting that it can be used for screening of H. contortus infections in livestock populations in epidemiological studies and the control of this important parasite.


Assuntos
Criação de Animais Domésticos/métodos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Hemoncose/veterinária , Haemonchus/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Animais , Bovinos , Hemoncose/diagnóstico , Hemoncose/parasitologia , Compostos Orgânicos/análise , Especificidade da Espécie , Turquia
2.
Crit Rev Anal Chem ; 50(1): 29-49, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30925844

RESUMO

This overview is focused to provide an useful guide of the families of organic pollutants that can be determined by liquid chromatography operating in reverse phase and ultraviolet/fluorescence detection. Eight families have been classified as the main groups to be considered: carbonyls, carboxyls, aromatics, phenols, phthalates, isocyanates, pesticides and emerging. The references have been selected based on analytical methods used in the environmental field, including both the well-established procedures and those more recently developed.


Assuntos
Cromatografia Líquida/métodos , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise , Fracionamento Químico/métodos , Monitoramento Ambiental/métodos , Espectrometria de Fluorescência/métodos , Espectrofotometria Ultravioleta/métodos
3.
Crit Rev Anal Chem ; 50(1): 1-28, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31204504

RESUMO

Aquatic passive samplers have been extensively tested and deployed in the field over the past two decades. Among these devices is relatively recently developed the Polar Organic Chemical Integrative Sampler (POCIS) for isolation of hydrophilic organic micropollutants in aquatic environment. The use of POCIS allows the measurement of low and fluctuating trace concentrations of such micropollutants, which is often troublesome using classical sampling. In this review, POCIS applications based on numerous articles to assess the suitability of these devices for use in environmental analytics information were summarized. Additionally, the possibilities of using POCIS for the isolation of complex chemical mixtures in order to highlight the high potential of this devices were presented. The types of sorbents used in POCIS, exposure duration and sampling media are juxtapose in this review. Based on the existing literature, attention was paid to both promising opportunities but also to limitations of passive methods.


Assuntos
Técnicas Biossensoriais/instrumentação , Monitoramento Ambiental/instrumentação , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise , Técnicas Biossensoriais/métodos , Monitoramento Ambiental/métodos , Fluorcarbonetos/análise
4.
Chemosphere ; 240: 124923, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726605

RESUMO

The purpose of this study is to deepen the knowledge of the various emission phenomena present in aerated tanks, widely used systems for municipal and industrial wastewater treatment. In order to investigate the emission mechanism, a specific model was developed. The theoretical model proposes to consider three different contributions to the emission of organic compounds from aerated wastewater tanks: the convection due to the sweep air flow rate, the rising bubbles stripping and the aerosol formation and successive evaporation. To compare the modeled results, an experimental campaign was conducted with two different solutes, acetone and butanol. The sampling was carried out with a Wind Tunnel system and the outflow gas samples were analysed with gas chromatographic technique. Moreover, this study investigates the dependence of the concentration in the gaseous phase from the speed of the air on the surface (1-5 cm/s) and from the flow of air diffused inside the liquid body (50-200 L/h). The empirical data were compared with theoretical curves. The results confirm two facts: the gas solute concentration decreases as the air velocity increases and, instead, increases with the air flow diffused through the tank.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Modelos Teóricos , Compostos Orgânicos/análise , Aerossóis/análise , Veículos Automotores , Águas Residuárias/análise
5.
Chemosphere ; 240: 124883, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726606

RESUMO

A coupled algal-osmosis membrane treatment system was studied for recovering potable-quality water from municipal primary effluent. The core components of the system included a mixotrophic algal process for removal of biochemical oxygen demand (BOD) and nutrients, followed by a hybrid forward osmosis (FO)-reverse osmosis (RO) system for separation of biomass from the algal effluent and production of potable-quality water. Field experiments demonstrated consistent performance of the algal system to meet surface discharge standards for BOD and nutrients within a fed-batch processing time of 2-3 days. The hybrid FO-RO system reached water productivity of 1.57 L/m2-h in FO using seawater as draw solution; and permeate flux of 3.50 L/m2-h in brackish water RO (BWRO) and 2.07 L/m2-h in seawater RO (SWRO) at 2068 KPa. The coupled algal-membrane system achieved complete removal of ammonia, fluoride, and phosphate; over 90% removal of calcium, sulfate, and organic carbon; and 86-89% removal of potassium and magnesium. Broadband characterization using high resolution mass spectrometry revealed extensive removal of organic compounds, particularly wastewater surfactants upon algal treatment. This study demonstrated long-term performance of the FO system at water recovery of 90% and with membrane cleaning by NaOH solution.


Assuntos
Reatores Biológicos/microbiologia , Água Potável/análise , Membranas Artificiais , Rodófitas/crescimento & desenvolvimento , Purificação da Água/métodos , Filtração/métodos , Compostos Orgânicos/análise , Osmose , Águas Salinas/química , Água do Mar/química , Águas Residuárias/química , Poluentes Químicos da Água/análise
6.
Chemosphere ; 238: 124573, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31454741

RESUMO

This study investigated the nutrient content and reuse potential of wastewater generated during hydrothermal liquefaction of microalgal biomass. The hydrothermal liquefaction reaction was tested at 270, 300, 330, and 345 °C to determine the effect of temperature on the formation of non-biodegradable dissolved organic nitrogen (nbDON). Total nitrogen, ammonium, color, and toxicity were selected as key characteristics for the reuse of hydrothermal liquefaction wastewater. Results indicated that a higher concentration of nbDON5 (nbDON defined with a 5 day growth assay) and more diverse heterocyclic N-containing organic compounds were associated with greater toxicity as measured by a growth rate assay. For the tested temperature ranges, the total nitrogen content of the hydrothermal liquefaction wastewater slightly decreased from 5020 ±â€¯690 mg L-1 to 4160 ±â€¯120 mg L-1, but the % nbDON5 fraction increased from 57 ±â€¯3 %DON to 96 ±â€¯5 %DON. The temperature of hydrothermal liquefaction reactions can be optimized to maximize carbon conversion and nitrogen recovery.


Assuntos
Chlorella/crescimento & desenvolvimento , Microalgas/crescimento & desenvolvimento , Compostos de Nitrogênio/toxicidade , Compostos Orgânicos/toxicidade , Águas Residuárias/toxicidade , Biodegradação Ambiental , Biocombustíveis , Biomassa , Nitrogênio/análise , Compostos de Nitrogênio/metabolismo , Compostos Orgânicos/análise , Temperatura Ambiente , Águas Residuárias/química
7.
Chemosphere ; 238: 124633, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31454747

RESUMO

Three different source waters were investigated using virgin and pre-used anion exchange resins, coagulation, and ion exchange combined with coagulation (IEX&Coagulation). The hydrophobicity, size distribution and charge of natural organic matter (NOM) were used to evaluate its removal. Dissolved organic carbon (DOC) removal by pre-used IEX resin was 67-79%. A consistent ratio of different hydrophobicity fractions was found in the removed DOC, while the proportion and quantity of the molecular weight fraction around 1 kDa was important in understanding the treatability of water. For pre-used resin, organic compounds were hypothesised to be restricted to easily accessible exchange sites. Comparatively, virgin resin achieved higher DOC removals (86-89%) as resin fouling was absent. Charge density and the proportion of the hydrophobic fraction were found to be important indicators for the specific disinfection byproduct formation potential (DBP-FP). Treatment of raw water with pre-used resin decreased the specific DBP-FP by between 2 and 43%, while the use of virgin resin resulted in a reduction of between 31 and 63%. The highest water quality was achieved when the combination of IEX and coagulation was used, reducing DOC and the specific DBP-FP well below that seen for either process alone.


Assuntos
Compostos Orgânicos/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Resinas de Troca de Ânions/química , Floculação , Interações Hidrofóbicas e Hidrofílicas , Troca Iônica
8.
Chemosphere ; 238: 124677, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524616

RESUMO

Understanding the health implications of human exposure to mixtures of chemical contaminants is aided by analytical methods that can screen for a broad range of both expected and unexpected compounds. We performed a proof-of-concept analysis combining human breast milk, a biomonitoring matrix for determining contaminant exposure to mothers and infants, with a non-targeted method based on comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC/TOF-MS). A total of 172 presumably anthropogenic halogenated compounds and non-halogenated cyclic and aromatic compounds were tentatively identified in breast milk from San Diego, California through mass spectral database searches. Forty of the compounds were prioritized for confirmation based on halogenation or 100% frequency of detection, and the identities of 30 were verified using authentic standards. Thirty-four (85%) of the prioritized contaminants are not typically monitored in breast milk surveys, and 31 (77%) are regulated in at least one market worldwide, indicating breast milk may be a useful biomonitoring matrix for non-targeted analysis and the assessment of human exposure to future emerging or undiscovered contaminants.


Assuntos
/estatística & dados numéricos , Leite Humano/química , Compostos Orgânicos/análise , California , Exposição Ambiental , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Halogenação , Humanos
9.
Chemosphere ; 240: 124928, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563101

RESUMO

Oxidation is an attractive treatment method to effectively remove organic contaminants in water. In this study, degradation of 30 organic compounds in different oxidation systems was evaluated, including oxygen (O2), hydrogen peroxide (H2O2), ozone (O3) and hydroxyl radical (HO). First, a quantitative structure-activity relationship (QSAR) model for oxidation-reduction potentials (ORPs) of organics was developed and exhibited a good performance to predict ORP values of organics with evaluation indices of squared correlation coefficient (R2) = 0.866, internal validation (q2) = 0.811 and external validation (Qext2) = 0.669. Four quantum parameters, including f(+)n, f(-)n, EHOMO and EB3LYP dominate the ORP values. Subsequently, a relationship between reaction rates (k) and the difference of ORP for oxidants and organics (ΔEoxi-org) was established, however, which was limited (R2= 0.697). Therefore, two new predictors (slopes and intercepts) are proposed based on the linear relationships between k values and ORPs of oxidants. These new predictors can be applied to estimate the reaction rates and minimum oxidation potential for organic compounds. Afterwards, to express the two predictors, QSAR models were established. The two optimal QSAR models fitted very well with experimental values and were demonstrated to be stable and accurate based on R2 (0.982 and 0.965), q2 (0.950 and 0.950) and Qext2 (0.985 and 0.989). BOx, q(H)+ and q(C)x were main factors influencing the slopes and intercepts. This study developed methods to predict ORPs of organics and established two new predictors to estimate the reaction rates undergoing different oxidation processes, offering new insights into the oxidant selection.


Assuntos
Modelos Teóricos , Compostos Orgânicos/análise , Relação Quantitativa Estrutura-Atividade , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Oxidantes/química , Oxirredução , Oxigênio/química , Ozônio/química , Águas Residuárias/química , Água
10.
Chemosphere ; 240: 124925, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563715

RESUMO

A study was conducted to understand the impact of reverse osmosis concentrate (ROC) characteristics on the efficacy of biological activated carbon (BAC) based treatments for removing organics and nutrients from two ROC streams (ROCa derived from municipal waste input with high salinity, and ROCb derived from domestic waste plus industrial trade waste with markedly lower salinity). Fluorescence excitation and emission matrix spectra and molecular weight analysis demonstrated that ROCa and ROCb had a significantly different composition of organic compounds due to the petrochemical processing and abattoir waste compounds in ROCb. Although the sequence of coagulation, UV/H2O2 and BAC gave the highest organic removal from the two ROCs (67% DOC for ROCa and 62% for ROCb), UV/H2O2 followed by BAC achieved satisfactory removal (>55%) for both ROC types. Sequential treatment involving coagulation gave better phosphorus removal (>90%) than any single treatment (<65%). Total nitrogen (TN) removal was fairly low (<50%) for all the treatment options and the salinity level had insignificant impact on nitrogen removal. Analysis of bacterial communities suggested that higher phosphorus removal and lower total nitrogen and nitrate removal from ROCb than ROCa was related to the presence of various denitrifying or phosphorus accumulating bacteria in the BAC.


Assuntos
Carvão Vegetal/química , Compostos Orgânicos/análise , Osmose , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Desnitrificação , Filtração/métodos , Peróxido de Hidrogênio/química , Nitrogênio/análise , Fósforo , Salinidade , Águas Residuárias/química
11.
Chemosphere ; 240: 124938, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31574444

RESUMO

Clearwater Mesa (James Ross Island, northeast Antarctic Peninsula) provides a unique opportunity to study solute dynamics and geochemical weathering in the pristine lacustrine systems of a high latitude environment. In order to determine major controls on the solute composition of these habitats, a geochemical survey was conducted on 35 lakes. Differences between lakes were observed based on measured physico-chemical parameters, revealing neutral to alkaline waters with total dissolved solids (TDS) < 2500 mg L-1. Katerina and Trinidad-Tatana systems showed an increase in their respective TDS, total organic carbon values, and finner sediments from external to internal lakes, indicating an accumulation of solutes due to weathering. Norma and Florencia systems exhibited the most diluted and circumneutral waters, likely from the influence of glacier and snow melt. Finally, isolated lakes presented large variability in TDS values, indicating weathering and meltwater contributions at different proportions. Trace metal abundances revealed a volcanic mineral weathering source, except for Pb and Zn, which could potentially indicate atmospheric inputs. Geochemical modelling was also conducted on a subset of connected lakes to gain greater insight into processes determining solute composition, resulting in the weathering of salts, carbonates and silicates with the corresponding generation of clays. We found CO2 consumption accounted for 20-30% of the total species involved in weathering reactions. These observations allow insights into naturally occurring geochemical processes in a pristine environment, while also providing baseline data for future research assessing the impacts of anthropogenic pollution and the effects of climate change.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Lagos/química , Minerais/análise , Compostos Orgânicos/análise , Oligoelementos/análise , Regiões Antárticas , Carbonatos/análise , Mudança Climática , Ecossistema , Camada de Gelo/química , Chumbo/análise , Trinidad e Tobago , Tempo (Meteorologia) , Zinco/análise
12.
Chemosphere ; 239: 124818, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31527002

RESUMO

This article is a short, but very important comment to the often used humification index (HIX), assumed to indicate the degree of biochemical degradation of dissolved organic matter in water samples. HIX is commonly calculated by dividing the fluorescence intensity detected at longer wave lengths by the intensity detected at shorter wavelengths. However, we found typos in the original article that affect the used equation directly and thus the results. We compared the different ways to calculate HIX and found a strong correlation between all results. Nevertheless, we recommend to use only equation 1, especially if data from different studies should be compared.


Assuntos
Compostos Orgânicos/análise , Solo/química , Espectrometria de Fluorescência/métodos , Revelação da Verdade , Dessecação , Fluorescência , Água/química
13.
Chemosphere ; 239: 124754, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31726531

RESUMO

We conducted the ecological risk assessment in an urban stream by using multiple-level approaches ranging from community level, chemical analyses in water and sediments, physiological assays of DNA biomarkers, embryonic development tests, and gene-level marker analyses of cyp1a, c-Fos, CRH, transgenic fli1:GFP and HuC:eGFP in zebrafish (Danio rerio). In water, the chemical perturbations based on nutrients (N,P), organic matter, ionic contents and metals identified in downstream zone. Analogous corroborations verified in sediment samples having hazardous metals (Zn, Pb, Cu, Ni, As, Cd). The chemical contaminations reflected significant damages in fish DNA, based on tDNA, tail length (TL), and tail extent moment (TEM). Zebrafish embryonic development experiments significantly enlightened the chemical contaminants in downstream compared to those in control and reference conditions. Hatching and survival rates rigorously declined in downstream region. Embryonic development delayed and followed by death in the downstream substantiated by the above-mentioned findings. Similar were the findings on heart rate and pigmentation largely affected in the contaminated zone. Pollutants in urban stream reflected significantly at the gene level, and were corroborated through experiments using transgenic zebrafish strains that were influenced by pollutants during the process of occurrence. In conclusion, these studies illuminate the community to gene-level ecological health assessment that could be useful for ecological risk assessments of urban streams and rivers. Further, the gene-level biomarkers and transgenic zebrafish experiments combination propose the procedures could be effectively used as sensitive and efficient biomarkers of ecological health and risk assessment in urban streams from community to gene-level assessments.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais Pesados/toxicidade , Compostos Orgânicos/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Animais , Biomarcadores/análise , Dano ao DNA/efeitos dos fármacos , Ecologia , Metais Pesados/análise , Compostos Orgânicos/análise , Medição de Risco , Rios/química , Poluentes Químicos da Água/análise
14.
Ecotoxicol Environ Saf ; 188: 109888, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31706242

RESUMO

Eutrophication can induce hypoxia/anoxia and rich organic matter at the sediment-water interface in surface waters. When eutrophic waters are impacted with mercury (Hg) pollution, methylmercury (MeHg) production ability (MPA) of surface sediment would increase and more MeHg might be produced. To tackle this risk, this study firstly collected samples of surface sediment and overlying water from a typical eutrophic lake-Taihu Lake. Then from a sediment-water simulation system, we demonstrated that eutrophic waters were able to methylate Hg spontaneously, and that sediment is the major Hg sink in the system. After the addition of HgCl2 solution (approximately 1 mg L-1 in the slurry), MeHg concentrations in the sediment increased by 11.7 times after 48 h. The subsequent column experiments proved that O2 nanobubbles could significantly decrease the MPA of surface sediment, by up to 48%. Furthermore, we found that O2 nanobubbles could remediate anoxia mainly by increasing dissolved oxygen (from 0 to 2.1 mg L-1), oxidation-reduction potentials (by 37% on average), and sulfate (by 31% on average) in the overlying water. In addition, O2 nanobubbles could also help decrease organic matter concentration, as was revealed by the decline of dissolved organic carbon in the overlying water (by up to 57%) and total organic carbon in surface sediment (by up to 37%). The remediation of anoxia and reduction of organic matter could contribute to the decrease of hgcA gene abundance (by up to 86%), and thus result in the reduction of MPA after the addition of O2 nanobubbles. This study revealed the risk of MeHg production in case Hg pollution occurs in eutrophic waters and proposed a feasible solution for MeHg remediation.


Assuntos
Recuperação e Remediação Ambiental/métodos , Sedimentos Geológicos/química , Compostos de Metilmercúrio/química , Oxigênio/química , Poluentes Químicos da Água/química , Eutrofização , Lagos/química , Mercúrio/análise , Mercúrio/química , Compostos de Metilmercúrio/análise , Compostos Orgânicos/análise , Compostos Orgânicos/química , Oxirredução , Oxigênio/análise , Poluentes Químicos da Água/análise
15.
J Sci Food Agric ; 100(1): 218-224, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31512242

RESUMO

BACKGROUND: Nowadays, fat replacement in meat products is a matter of concern in the meat industry. The objective of this study was to evaluate the replacement of pork backfat with two oleogels of linseed in dry-cured sausages. RESULTS: Five batches of dry-cured sausages were prepared with two oleogels, a mixture of γ-oryzanol and ß-sitosterol (SO) and beeswax (B), at two levels of replacement (20% and 40%) (SO-20, SO-40, B-20, and B-40, respectively) and a control batch. The fatty acid profile improved in terms of nutrition: the polyunsaturated fatty acid / saturated fatty acid (PUFA/SFA) and n-6/n-3 ratio was about 1.41 and 0.93 for the higher levels of replacement, SO-40 and B-40, respectively. Quality parameters such as pH and color also changed with the inclusion of oleogels, resulting in changes in the sensory quality. CONCLUSION: Oleogels based on linseed enabled the replacement of pork backfat in fermented sausages. Depending on the level of fat substitution, such oleogels could replace fat in dry-cured sausages at the industrial level. © 2019 Society of Chemical Industry.


Assuntos
Substitutos da Gordura/análise , Manipulação de Alimentos/métodos , Óleo de Semente do Linho/análise , Produtos da Carne/análise , Animais , Ácidos Graxos/análise , Fermentação , Humanos , Compostos Orgânicos/análise , Suínos , Paladar
16.
Anal Bioanal Chem ; 411(28): 7341-7355, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31667564

RESUMO

Over two decades, the Organic Analysis Working Group (OAWG) of the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM) has organized a number of comparisons for clinically relevant small molecule organic biomarkers. The aim of the OAWG community is to be part of the coordinated international movement towards accuracy and comparability of clinical measurements that will, in turn, minimize the wastage of repeat testing and unnecessary therapy to create a sustainable healthcare industry. International and regional directives/requirements on metrological traceability of calibrators and control materials are in place. Metrology institutes worldwide maintain infrastructure for the practical realization of metrological traceability and demonstrate the equivalence of their measurement capabilities through participation in key comparisons organized under the auspices of the CCQM. These institutes provide certified reference materials, as well as other dedicated value-assignment services benefiting the in-vitro diagnostic (IVD) industry, reference (calibration) laboratories and the clinical chemistry laboratories. The roles of these services in supporting national, regional, and international activities to ensure the metrological traceability of clinical chemistry measurements are described. Graphical abstract.


Assuntos
Biomarcadores/análise , Compostos Orgânicos/análise , Bibliotecas de Moléculas Pequenas/análise , Calibragem , Testes de Química Clínica , Humanos , Técnicas In Vitro , Padrões de Referência , Reprodutibilidade dos Testes
17.
Environ Monit Assess ; 191(11): 699, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667650

RESUMO

Effects of industrial and municipal wastewaters on the freshwater snail, Lanistes carinatus, were evaluated. Concentrations of some chemicals in some effluents were greater than permissible limits promulgated internationally by various jurisdictions. Pesticides and polychlorinated biphenyls (PCBs) observed in tissues of snails collected during summer were greater than those measured in snails collected during winter. Catalase activities observed during autumn were greater than those observed during other seasons. Activities of catalase were greater at all sites near sources of contamination than in snails from the reference site (S6). Lactate dehydrogenase activity was also greater at all sites relative to the location designated as the reference (S6), at which activities did not exceed 8.10 U/L. Patterns of genomic DNA in snails, as determined by use of OPA-02 primer, were significantly different among sites. Location S1 (Belshay village) exhibited 11 bands, followed by S2 (El-Demer zone) and S5 (Rosetta branch) which exhibited 6 bands. In contrast, all sites exhibited greater numbers of bands when the OPA-08 primer was used. Thus, DNA fingerprinting, lactate dehydrogenase, and catalase offer useful biomarkers in ecotoxicology and risk assessment programs.


Assuntos
Monitoramento Ambiental , Compostos Orgânicos/toxicidade , Caramujos/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Catalase , Ecotoxicologia , Egito , Água Doce , Compostos Orgânicos/análise , Praguicidas , Bifenilos Policlorados , Estações do Ano , Poluentes Químicos da Água/análise
18.
Environ Monit Assess ; 191(12): 734, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31707592

RESUMO

The quality of drinking water source remains as a major concern in areas of developing and underdeveloped countries worldwide. The treatment and supply of drinking water in Rwanda are carried out by Water and Sanitation Corporation, a state-owned public company. However, it is not able to supply water to all households. Consequently, the non-serviced households depend on natural water sources, like springs, to meet their water requirements. Nevertheless, the water quality in these springs is scarcely known. Therefore, this study assessed and compared metal elements in drinking water sources in the dry and rainy seasons in 2017 using the contamination degree, metal index, and geographic information systems to reveal the spatial distribution of water quality within the considered water sources of springs in Rwanda. The samples were collected monthly from nine water sources of springs and the measured elements are aluminium, calcium, copper, iron, manganese, and zinc. The metal index indicated that during the dry season and rainy season, the sites of Kibungo (1.10 and 1.26) and Kinigi (1.01 and 1.54) have assessed a metal index which is higher than 1. Thus, the water quality of those sites was getting the threshold of warning. The analysis indicated that pollutants are easily transported into water bodies during the rainy season in urban and rural areas to a greater extent than during the dry season .


Assuntos
Água Potável/análise , Monitoramento Ambiental , Sistemas de Informação Geográfica , Poluentes Químicos da Água/análise , Abastecimento de Água/estatística & dados numéricos , Cádmio/análise , Cobre/análise , Ferro/análise , Metais/análise , Compostos Orgânicos/análise , Chuva , Ruanda , Estações do Ano , Poluentes Químicos da Água/normas , Qualidade da Água , Zinco/análise
19.
Environ Monit Assess ; 191(11): 659, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31630273

RESUMO

A major campaign was carried out in indoor and outdoor environments in a school located in the university campus of the city of São Paulo. Elements, PAH, oxy-PAH, water-soluble ions and black carbon were determined and compared with preliminary campaigns. The results indicated that the concentrations of particles and organic compounds were higher indoors. Some high molecular weight compounds, attributed to vehicular emissions, were more abundant outdoors. The associated health risk was found to be low. 2-Methylanthraquinone and benzo(a)anthracene-7,12-dione were detected in the indoor samples, denoting the infiltration of vehicle exhaust. The observation of black carbon also corroborates the contribution of traffic emissions. For most of the elements, except for chromium, iron and manganese, the concentrations obtained in indoors were higher than outdoors, mainly due to soil resuspension. Chromium and manganese likely derived from emissions of the vehicle powered by mixtures of ethanol and gasoline. Water-soluble inorganic ions species denoted the influence of soil resuspension and human activities.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Instituições Acadêmicas/normas , Brasil , Cidades , Humanos , Compostos Orgânicos/análise , Material Particulado/análise , Solo/química , Emissões de Veículos/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-31540379

RESUMO

Transitional water ecosystems are targeted by the European Union (EU) Water Framework Directive (WFD, CE 2000/60) monitoring programs in coastal zones. Concerning sediments, activities performed for the WFD focus on a few variables concerning the biochemical composition of organic matter. Our research reports the effects of oxygen availability on the biochemical composition of organic matter in sediments to highlight levels of targeted variables in time and, according to the depth of sediment layer, both under oxygenated and anoxic conditions in a mesocosm study on sediment cores. Results provide evidence that tested factors of interest (i.e., disturbance type, oxygenic versus anoxic conditions; persistence time of disturbance, 0-14 days; penetration through sedimentary layers, 0-10 cm depth) are able to significantly affect the biochemical composition of organic matter in sediments. Large part of the variables considered in this study (total organic carbon (TOC), total phosphorous (TP), total sulphur (TS), Fe, carbohydrates (CHO), total proteins (PRT), biopolymeric carbon (BPC), chlorophyll-a (Chl-a) are significantly affected and correlated to the oxygenation levels and could be good early indicators of important changes of environmental conditions. Monitoring activities performed under WFD guidelines and management strategies of Mediterranean coastal lagoon ecosystems shall include the biochemical composition of organic matter in sediment to provide an exhaustive picture of such dynamic ecosystems.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Compostos Orgânicos/análise , Oxigênio/análise , Itália , Mar Mediterrâneo
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